This invention concerns physical blends of poly(1,3-propylene 2,6-naphthalate) polymer compositions with other polymers in which the concentration of poly(1,3-propylene 2,6-naphthalate) is from 1 to 99 mole %.
This invention relates to blends of poly(1,3-propylene 2,6-naphthalate) polymers (referred to herein as 3GN polymers or 3GN) with other polymers.
U.S. Pat. No. 3,937,754 discloses a biaxially oriented polyethylene 2,6-naphthalate (PEN) film which comprises PEN containing no more than 10 mole % of non PEN forming components and 0.5 to 10% of a polyester containing at least 90 mole % of a homopolyester unit other than PEN, having a softening point at least 1xc2x0 C. higher than its equilibrium softening point. Patentees teach that improvements in resistance to thermal degradation and Young""s modulus are achieved after the softening point of the PEN resin has decreased and before it decreases to a point at least 1xc2x0 C. higher than its equilibrium softening point. Thus, patentees teach that some, but not complete, reaction between the polyesters is necessary to achieve their desired advantages.
It is an object of the present invention to provide physical blends in which essentially no reaction between polymer components occur.
The present invention relates to compositions comprising physical blends of poly(1,3-propylene 2,6-naphthalate) polymer compositions with one or more second polymers in which the concentration of 3GN is from 1 to 99 mole % and in which essentially no reaction between the polymer components has taken place.